The Legal Subject as Continuant: Durability as a Hidden Assumption of Legal Subjecthood

Legal scholarship has extensively examined whether artificial agents and other novel entities should be recognised as legal persons. This article argues that this debate presupposes a more fundamental condition of legal subjecthood: the assumption that a legal subject is a continuant, namely, a single identifiable bearer that persists as numerically the same between the creation of a legal position and the legal response to it. Although this assumption is not expressly codified, it underlies legal doctrines developed around human subjects, whose continuity has historically been treated as given. The article demonstrates this assumption through two doctrinally unrelated areas: the coincidence of actus reus and mens rea in criminal responsibility and the identity-of-parties requirement underlying res judicata in civil procedure. The recurrence of the same continuity requirement across these domains indicates that persistence is not merely a feature of particular doctrines but a structural condition of legal subjecthood itself. The article further argues that corporate-style legal fictions cannot resolve this problem where the persistence of the underlying bearer is itself uncertain, because such fictions presuppose the continuity they seek to establish. The argument is diagnostic rather than prescriptive: it identifies a foundational assumption of modern legal subjecthood and shows how reconfigurable, copyable, and dissolving entities reveal its limits.